If you are still having this network issues with your Slingbox, probably the issue is being caused by the router, it's changing the IP assigned to the Slingbox very often, I recommend trying to create a static IP to the Slingbox and after setting up port forwarding on the router, run the Setup at Slingbox.com and select the manual setup for Internet Viewing, enter the IP and port information, the test should go through and you should not experience this issue anymore. Check this out: